Biomedical subjects

D J Kim

Publications and source records attributed to D J Kim.

At least 109 records · Page 6Linked to original sources

PubMed1999

Correlation of laminated MR appearance of articular cartilage with histology, ascertained by artificial landmarks on the cartilage.

The object of this study was to correlate the laminae of articular cartilage on magnetic resonance (MR) imaging with histologic layers. T1- and fast spin-echo T2-weighted images of articular cartilage with artificial landmarks were obtained under high gradient echo strength (25 mT/m) conditions and a voxel size of 78 x 156 x 2000 microm. Images were also obtained with a) changed frequency-encoding directions; b) changed readout gradient strength; and c) a varied number of phase-encoding steps. T2 mapping was performed with angular variations. Artificial landmarks allowed accurate comparison between the laminae on MR images and the histologic zones. No alterations of the laminae were noted by changing the frequency gradient direction. Altering readout gradient strengths did not show a difference in the thickness of the laminae, and increasing the phase-encoding steps resulted in a more distinct laminated appearance, ruling out chemical shift, susceptibility, and truncation artifacts. The T2 mapping profile showed an anisotropic angular dependency from the magic angle effect. In conclusion, the laminated appearance of articular cartilage on spin-echo and fast spin-echo MR images correlated with the histologic zones rather than MR artifacts.

Animals↗

PubMed1999

Intra-articular ganglion cysts of the knee.

A ganglion is a cystic mass with myxoid matrix that occasionally occurs within muscles, tendons, and menisci. A ganglion cyst within the knee is very rare, with few reports to be found. We are reporting eight cases of a ganglion within the knee joint. Our cases include two ganglia in the infrapatellar fat pad which have not been previously reported. Ganglion cysts do not have specific symptoms. We hypothesize that symptoms of a ganglion cyst may correlate with the size and the location within the knee joint. The diagnosis of ganglia within the knee was established by magnetic resonance imaging study and confirmed by pathological testing. All the patients were treated successfully using the arthroscopic technique.

Adolescent↗

PubMed1999

Production and characterization of monoclonal antibodies against human airway mucins.

The objective of this study was to generate and characterize monoclonal antibodies (MAbs) against human airway mucins, and therefore, should serve as a useful tool in studying the regulation of airway mucins in various physiological or pathological situations of human airway. As an antigen, we used a high molecular mass mucin preparation purified from the sputum of normal human subjects. Two monoclonal hybridomas, namely MAbs HM02 and HM03 were obtained and they showed strong immunoreactivity against purified or crude mucin in sputum or bronchial washing of normal human subject. With the high immunoreactivity of these MAbs, mucin contents could be analyzed with more than 100-fold dilution of human airway secretion. The antibodies recognized carbohydrate epitopes because their immunoreactivity was completely abolished by treatment of the mucin with 5 mM periodate. Further characterization of MAbs HM02 and HM03 showed that: (1) they belong to the IgM type; (2) they bind to high molecular mass mucins based on Western blot; (3) they could indirectly immunoprecipitate human airway mucin and as we know, this is the first to demonstrate immunoprecipitation of human airway mucin with anti-human mucin antibodies; and (4) they bind to the goblet cell in airway epithelium as well as some submucosal glands based on immunohistochemistry. Therefore, MAbs HM02 and HM03 should be able to serve as an invaluable tool in studying the regulation of airway mucins in various physiological and pathological situations of human airway.

Animals↗

PubMed1999

Immunohistochemical localization of inducible nitric oxide synthase and 3-nitrotyrosine in rat liver tumors induced by N-nitrosodiethylamine.

Human liver cancers have been associated mainly with chronic inflammations such as viral hepatitis B or C. This suggests that prolonged cell damage by chronic inflammation is critical in cancer development. Overproduction of nitric oxide (NO.) and its derivative (NOx, peroxynitrite) has been implicated as a cause of tissue damage by inflammation, thus contributing to tumor promotion. We have demonstrated the expression of the inducible isoform of nitric oxide synthase (iNOS) and 3-nitrotyrosine, a marker of peroxynitrite formation, by immunohistochemistry in preneoplastic and neoplastic rat liver tissues induced by continuous infusion of N-nitrosodiethylamine with mini-pumps. The preneoplastic lesions were characterized by proliferation of phenotypically altered hepatic foci (PAHF), dysplastic hepatocytes and oval cells. Histologically, the tumors were hepatocellular carcinomas (HCCs) of trabecular, (pseudo)glandular and solid types with or without cholangiocellular involvement. iNOS was located mainly in oval cells, capillary endothelial and muscular cells, epithelia of cholangiomas and glandular HCCs. 3-Nitrotyrosine was observed in the cytoplasms of PAHF and dysplastic hepatocytes in preneoplasias and in the cytoplasms of some living or apoptotic HCC cells, connective tissues, proteinaceous fluids, sinusoidal endothelia of tumorous hepatocytes and cholangiomas in tumors. From these observations, we suggest that: (i) chronic tissue damage by chemical carcinogens may act to induce iNOS and peroxynitrite formation; (ii) oval cells play a key role in development and/or growth of tumor tissues by producing NO. via iNOS, which may also cause tissue damage by peroxynitrite; (iii) iNOS can be considered as a phenotypic marker in cells of oval cell lineage and neovascularized capillaries in tumor tissues.

Adenoma, Bile Duct↗

PubMed1999

Attachment of the deep temporal fascia to the zygomatic arch: an anatomic study.

It is generally acknowledged that the superficial layer of the deep temporal fascia attaches to the lateral surface and its deep layer along the medial surface of the zygomatic arch. However, Ramírez asserts that the superficial and the deep layer of the deep temporal fascia fuse consistently approximately 1 cm above the upper ridge of the arch and attach to the outer surface of the arch, blending with the superficial fascia of the masseter muscle. In this study the authors clarify the precise anatomic relations between the fascia and the zygomatic arch. Coronal sections crossing the midpoint between the zygomaticotemporal suture and the tubercle of zygoma were observed grossly and histologically in 32 hemifaces from 16 Korean adult cadavers. This study demonstrates that the superficial and the deep layers of the deep temporal fascial fuse and insert onto the superior margin of the arch in 18 dissections (56%) and insert onto the superolateral surface in 14 dissections (44%). The contacting surface of the fused deep temporal fascia to the periosteum of the zygomatic arch is less than 2 mm. The following route is safer and is recommended for reaching the zygomatic arch region: Just above the split of the deep temporal fascia, a dissection is carried through the deep temporal fasica, continuing downward to the superior margin of the arch along the undersurface of the fascia. At this spot the periosteum of the arch is dissected.

Adult↗

PubMed1999

Induction of neutralizing antibody against human cytomegalovirus (HCMV) with DNA-mediated immunization of HCMV glycoprotein B in mice.

Immunization was accomplished by inoculating pcGB containing human cytomegalovirus (HCMV) glycoprotein B (gB) gene into BALB/c mice intramuscularly. IgM antibody was detected in all the immunized group. IgG antibody was also found in all the tested mice with a mean peak antibody titer of 1:262 in three-times immunized groups. IgG antibody appeared at 2 weeks postinoculation, raised peak levels at 7 weeks postinoculation and persisted over 6 months. Neutralizing antibody was developed, and the percent reduction of input infectivity in 1:100 diluted sera was 74.5 % in three-times immunized groups. This study suggested that DNA vaccine using the gene encoding HCMV gB is a candidate method for developing immunity to HCMV.

Animals↗

PubMed1999

Discordant evolution of asymptomatic proteinuria in identical twins.

We describe a pair of 17-year-old identical twin brothers with asymptomatic proteinuria, one of whom showed focal segmental glomerulosclerosis (FSGS) while the other showed immunoglobulin M (IgM) nephropathy. For each twin, audiological examination was normal. There was no family history of renal failure, deafness, or hematuria. HLA typing revealed an identical phenotype consisting of A25, A33, B44, B54, Cw1, Cw7, DR7 and DRB1. There is still controversy about whether minimal change disease, IgM nephropathy, and FSGS are discrete entities or different aspects of the same disease. The coexistence of IgM nephropathy and FSGS in identical twins suggests that the same genetic factors may be involved in the development of both diseases. However, although the brothers are identical twins, they had different eating habits and body weight. The twin who preferred to eat a protein-rich diet and who was heavier developed early proteinuria and manifested FSGS on renal biopsy. The discordant evolution of asymptomatic proteinuria in identical twins may provide a clue for the existence of environmental factors on the progression from IgM nephropathy to FSGS. Therefore, this report provides indirect support for the hypothesis that IgM nephropathy and FSGS represent different aspects in the spectrum of a single disease.

Adolescent↗

PubMed1999

Neural toxicity induced by accidental intrathecal vincristine administration.

Described here is a case of accidental intrathecal administration of vincristine with pathologic findings in the central nervous system. A 3-year-old boy with acute lymphoblastic leukemia, was given his ninth course chemotherapy. Vincristine was accidentally injected intrathecally. The clinical course was rapidly progressive (6-day course) and resulted in death. An autopsy was done. The brain and spinal cord was grossly edematous and congested without any specific feature. Histologically, profound loss of neuron was noted in the spinal cord. Remaining neurons in the spinal cord, particularly anterior horn cells were markedly swollen. The spinal nerves show diffuse axonal degeneration and myelin loss. The upstream portion of the spinal cord (brain stem, cerebellum, cerebrum) showed patchy loss of neurons, especially Purkinje cells and granular cells of the cerebellar cortex. Many neurons showed axonal reaction (chromatolysis) with swelling. Several neurons show intracytoplasmic eosinophilic inclusion body. Myelin loss, axonal swelling and enlargement of perivascular spaces were seen throughout the white matter of central nervous system.

Antineoplastic Agents↗

PubMed1999

The effect of continuous ambulatory peritoneal dialysis on change in serum leptin.

OBJECTIVE: Elevated serum leptin can contribute to anorexia and poor nutrition in patients with chronic renal failure, because leptin is elevated in chronic renal failure patients with or without dialysis, especially in chronic ambulatory peritoneal dialysis (CAPD) patients. The aim of this study was to find whether leptin can be removed by peritoneal dialysis (PD) and to analyze factors that can affect serum leptin after start of CAPD by observing the change in serum leptin shortly after start of CAPD and its correlation with body mass index (BMI), with serum insulin, and with residual renal function. DESIGN: Twenty patients who started CAPD during the observation period were studied. Serum leptin was measured by radioimmunoassay before start of CAPD, 3-5 days after start of CAPD, and 1 month and 3 months after start of CAPD. Simultaneously, body weight, serum insulin, and residual renal function were measured. To compensate for the circardian rhythm of leptin, removal of leptin was assessed by measuring dialysate leptin divided by average serum leptin before and after a peritoneal equilibration test (PET). RESULTS: Leptin was eliminated by PD with a dialysate-to-serum ratio of 0.16+/-0.07, which was comparable to removal of beta2-microglobulin (0.14+/-0.06). The mean serum leptin concentrations did not decrease after 3-5 days of CAPD (8.4+/-13.1 ng/mL-->11.9+/-18.0 ng/mL) despite its removal by PD, and levels increased markedly to 189% of basal serum leptin 1 month after start of PD and to 260% of basal serum leptin 3 months after start of PD. Correlation coefficients (Spearman's rho) between change of serum leptin and change of BMI, of serum insulin, of glomerular filtration rate (average of urine creatinine clearance and urine urea clearance) were 0.267 (p > 0.05, n = 20), 0.441 (p > 0.05, n = 16), 0.706 (p > 0.05, n = 8) respectively. CONCLUSION: Leptin is removed by peritoneal dialysis. Serum leptin did not decrease in 5 days after the start of PD despite its removal by PD, but increased markedly thereafter, within 3 months after start of PD. We could not find a significant correlation between the change in leptin and the change in BMI. Factors other than fat-mass gain can stimulate leptin increase shortly after start of PD.

Adipose Tissue↗

PubMed1999

The effect of dialysate dwell on gastric emptying time in patients on continuous ambulatory peritoneal dialysis.

METHODS AND PATIENTS: We evaluated gastric emptying time (GET) with a technetium (Tc) 99m-sulfur colloid gastric emptying scan in 11 patients on continuous ambulatory peritoneal dialysis (CAPD) (6 males, 5 females) and in 14 controls. We investigated the effect of dialysate dwell on GET by studying the subjects twice: once without dialysate in the abdomen (drained) and once with 2 L of dialysate in the abdomen (full). We also investigated the relationship between body surface area (BSA) and delayed gastric emptying. RESULTS: (1) The mean gastric emptying rate in 120 minutes in patients on CAPD when drained (67.8%+/-13.4%) was not different from that in controls (65.4%+/-8.6%). (2) The mean gastric emptying rate in 120 minutes in patients on CAPD when full was significantly slower than that when drained (55.6%+/-14.6% versus 67.8%+/-13.4%, p < 0.05). In four of the 11 patients (36.4%), gastric emptying was extremely delayed from normal to abnormal range when full. (3) The BSA of patients who had extremely delayed GET from normal to abnormal range was smaller than that of patients who had minimal delayed or unchanged GET when full (1.5+/-0.11 m2 versus 1.74+/-0.22 m2). CONCLUSION: This study showed that patients on CAPD had normal gastric emptying when drained, and that gastric emptying was delayed by dialysate dwell, especially in patients who has less than 1.5 m2 of body surface area. Therefore, we suggest that, based on adequacy, intermittent nocturnal peritoneal dialysis or a small volume of dialysate be considered for patients with small body surface area.

Dialysis Solutions↗

PubMed1999

Asian Pacific cooperative study of allogeneic bone marrow transplantation.

The first cooperative study of the Asian Pacific bone marrow transplantation group included 75 patients with early leukemia who received human leukocyte antigen-matched sibling bone marrow transplants and were randomized into granulocyte colony-stimulating factor and control groups. The selected patients were registered from 10 centers in six countries and areas within Asia (Beijing, Taipei, Hong Kong, Japan, Korea, and Malaysia). The incidence of grades II-IV acute graft-vs.-host disease was 22.2%, and the 2-year survival rate was 62.7%. The period of protective isolation (27.1-66.7 days), period of hospitalization (38.6-130.5 days), and medical costs for 4 months (US $10,300-US $80,803) varied considerably. Good cooperation, i.e., low rate of protocol violation or rapid and precise presentation of case reports, was obtained.

Bone Marrow Transplantation↗

PubMed1998

Structure-activity studies related to ABT-594, a potent nonopioid analgesic agent: effect of pyridine and azetidine ring substitutions on nicotinic acetylcholine receptor binding affinity and analgesic activity in mice.

Analogs of A-98593 (1) and its enantiomer ABT-594 (2) with diverse substituents on the pyridine ring were prepared and tested for affinity to nicotinic acetylcholine receptor binding sites in rat brain and for analgesic activity in the mouse hot plate assay. Numerous types of modifications were consistent with high affinity for [3H]cytisine binding sites. By contrast, only selected modifications resulted in retention of analgesic potency in the same range as 1 and 2. Analogs of 2 with one or two methyl substituents at the 3-position of the azetidine ring also were prepared and found to be substantially less active in both assays.

Alkaloids↗

PubMed1998

Osteoblastic phenotype of rat marrow stromal cells cultured in the presence of dexamethasone, beta-glycerolphosphate, and L-ascorbic acid.

We investigated the effects of the time course of addition of osteogenic supplements dexamethasone, beta-glycerolphosphate, and L-ascorbic acid to rat marrow stromal cells, and the exposure time on the proliferation and differentiation of the cells. It was the goal of these experiments to determine the time point for supplement addition to optimize marrow stromal cell proliferation and osteoblastic differentiation. To determine this, two studies were performed; one study was based on the age of the cells from harvest, and the other study was based on the duration of exposure to supplemented medium. Cells were seen to proliferate rapidly at early time points in the presence and absence of osteogenic supplements as determined by 3H-thymidine incorporation into the DNA of replicating cells. These results were supported by cell counts ascertained through total DNA analysis. Alkaline phosphatase (ALP) activity and osteocalcin production at 21 days were highest for both experimental designs when the cells were exposed to supplemented medium immediately upon harvest. The ALP levels at 21 days were six times greater for cells maintained in supplements throughout than for control cells cultured in the absence of supplements for both studies, reaching an absolute value of 75 x 10(-7) micromole/min/cell. Osteocalcin production reached 20 x 10(-6) ng/cell at 21 days in both studies for cells maintained in supplemented medium throughout the study, whereas the control cells produced an insignificant amount of osteocalcin. These results suggest that the addition of osteogenic supplements to marrow-derived cells early in the culture period did not inhibit proliferation and greatly enhanced the osteoblastic phenotype of cells in a rat model.

Alkaline Phosphatase↗

PubMed1998

ABT-594, a novel cholinergic channel modulator, is efficacious in nerve ligation and diabetic neuropathy models of neuropathic pain.

A novel cholinergic channel modulator, ABT-594, was tested in two established and distinct models of neuropathic pain; the Chung model (i.e., tight ligation of L5 and L6 spinal nerves) and a diabetic neuropathy model (i.e., streptozotocin-induced diabetes). Tactile allodynia and mechanical hyperalgesia were assessed in the Chung and diabetic neuropathy models, respectively. ABT-594 produced a significant antiallodynic effect following both oral (0.1-1 micromol/kg) and intraperitoneal (i.p.) (0.3 micromol/kg) administration. Equal efficacy was observed following both routes of administration. ABT-594 (0.3 micromol/kg, i.p.) maintained efficacy following repeated dosing (5 days; twice daily) in the Chung model, but the effect of morphine (21 micromol/kg, i.p.) was significantly reduced after repeated dosing. In the diabetic neuropathy model, ABT-594 (0.3 micromol/kg, i.p.) effectively reduced mechanical hyperalgesia. Morphine (21 micromol/kg, i.p.) was not effective in this model. Overall, these results suggest development of ABT-594 may provide a novel pharmacotherapy for the chronic treatment of neuropathic pain.

Administration, Oral↗

PubMed1998

Synthesis and biological properties of new 1 beta-methylcarbapenems.

The synthesis and biological activity of the novel series of 1 beta-methylcarbapenems, 1 and 2 were described. Most compounds displayed high potent antibacterial activity. The best compound in this series, 2a (IH201; R2 = NH2) showed an excellent and a broad spectrum as well as high renal DHP-I stability. It also possessed good in vivo efficacy and high safety.

Animals↗

PubMed1998

Antinociceptive effects of the novel neuronal nicotinic acetylcholine receptor agonist, ABT-594, in mice.

ABT-594 [5-((2R)-azetidinylmethoxy)-2-chloropyridine], a novel neuronal nicotinic acetylcholine receptor agonist, produced significant antinociceptive effects in mice against both acute noxious thermal stimulation--the hot-plate and cold-plate tests--and persistent visceral irritation--the abdominal constriction (writhing) assay (maximally-effective dose in each test 0.62 micromol/kg, i.p.). This effect was not stereoselective since the S-enantiomer, A-98593 [5-((2S)-azetidinylmethoxy)-2-chloropyridine], produced similar antinociceptive effects in this dose range. The effect in the hot-plate test peaked at 30 min after i.p. administration and was still present 60 min, but not 120 min, after injection. ABT-594 was orally active, but 10-fold less potent by this route than after i.p. administration. The antinociceptive effect of ABT-594 was prevented, but not reversed, by the noncompetitive neuronal nicotinic acetylcholine receptor antagonist mecamylamine (5 micromol/kg, i.p.). In contrast, the antinociceptive effect of ABT-594 was not prevented by hexamethonium (10 micromol/kg, i.p.), a neuronal nicotinic acetylcholine receptor antagonist that does not readily enter the central nervous system, nor by naltrexone (0.8 micromol/kg), an opioid receptor antagonist. Thus, initiation of antinociception by ABT-594 involves activation of central nicotinic acetylcholine receptors, but does not require activation of naltrexone-sensitive opioid receptors. The antinociceptive effects of morphine and ABT-594 in the mouse hot-plate test appeared to be additive, but ABT-594 did not potentiate the respiratory depression produced by morphine when the two compounds were coadministered. ABT-594 reduced body temperature and spontaneous exploration in the antinociceptive dose range, but did not reliably impair motor coordination in the rotarod test. Thus, it is unlikely that the antinociceptive effects result simply from impaired motor function. The compound also produced an anxiolytic-like effect in the elevated plus maze (at 0.019 and 0.062 micromol/kg, i.p.). Preliminary safety testing revealed an ED50 for overt seizure production of 1.9 micromol/kg, i.p. and an LD50 of 19.1 micromol/kg i.p. in mice, values 10 and 100 times the minimum effective antinociceptive dose of the compound. ABT-594 increased the duration of ethanol-induced hypnotic effects, tended to increase pentobarbital-induced hypnotic effects (P = 0.0502), and had no effect on pentobarbital-induced lethality. These data indicate that ABT-594 is a centrally acting neuronal nicotinic acetylcholine receptor agonist with potent antinociceptive and anxiolytic-like effects in mice.

Analgesics, Non-Narcotic↗

PubMed1998

Identification and initial structure-activity relationships of (R)-5-(2-azetidinylmethoxy)-2-chloropyridine (ABT-594), a potent, orally active, non-opiate analgesic agent acting via neuronal nicotinic acetylcholine receptors.

New members of a previously reported series of 3-pyridyl ether compounds are disclosed as novel, potent analgesic agents acting through neuronal nicotinic acetylcholine receptors. Both (R)-2-chloro-5-(2-azetidinylmethoxy)pyridine (ABT-594, 5) and its S-enantiomer (4) show potent analgesic activity in the mouse hot-plate assay following either intraperitoneal (i.p.) or oral (p.o.) administration, as well as activity in the mouse abdominal constriction (writhing) assay, a model of persistent pain. Compared to the S-enantiomer and to the prototypical potent nicotinic analgesic agent (+/-)-epibatidine, 5 shows diminished activity in models of peripheral side effects. Structure-activity studies of analogues related to 4 and 5 suggest that the N-unsubstituted azetidine moiety and the 2-chloro substituent on the pyridine ring are important contributors to potent analgesic activity.

Administration, Oral↗

PubMed1998

Synthesis and antibacterial activities of new carbapenems having a proline reverse amide moiety at the C-2 position.

The synthesis of new 1 beta-methylcarbapenems (1a-l) having a proline reverse amide moiety at the C-2 position and their in vitro antibacterial activities are described. The compounds were evaluated by the Mueller-Hinton agar dilution method and compared with meropenem as control. Aliphatic amides (1a-h) are found to show greater antibacterial activity than aromatic amides (1i-l). Moreover, C-2 free amino compound (1m) reveals greater activity than any other amide compounds (1a-l).

Anti-Infective Agents↗